This letter proposes three distinct modulation schemes belonging to the class of rotated color-shift keying (CSK) to improve the performance of regular CSK over a tricolor visible light communications (VLC) channel subject to signal-dependent noise (SDN). In such channels, regular CSK schemes suffer from a severe constellation distortion. The proposed rotated CSK schemes termed respectively separative whitening-like rotation (SWR), multiplicative whitening-like rotation (MWR), and additive whitening-like rotation (AWR), provide error rate gains relative to the regular CSK. The proposed modulations are carried out by employing practical lighting constraints, including a relaxed color constraint by the MacAdam ellipses with appropriate steps.

中文翻译：

---

用于具有信号相关噪声的可见光通信的旋转色移键控

这封信提出了属于旋转色移键控 (CSK) 类别的三种不同调制方案，以提高受信号相关噪声 (SDN) 影响的三色可见光通信 (VLC) 信道上常规 CSK 的性能。在此类信道中，常规 CSK 方案遭受严重的星座失真。所提出的旋转 CSK 方案分别称为分离类白化旋转 (SWR)、乘法类白化旋转 (MWR) 和加性类白化旋转 (AWR)，提供相对于常规 CSK 的错误率增益。建议的调制是通过采用实际的照明约束来执行的，包括麦克亚当椭圆的宽松颜色约束和适当的步骤。